Second half strikes from Pape Diop and Felipe Caicedo saw Espanyol move seven points clear of the drop zone.
The first chance of the game came just before 10 minutes had been played at Cornella El-Prat when Mikel Rico found Oscar De Marcos inside the box with a beautiful pass, but the latter could only blaze his shot well over the bar.
Minutes later Athletic Club had another chance to take the lead when top goalscorer Aritz Aduriz found Rico at the back post, but his shot went straight into the grateful hands of Espanyol goalkeeper Pau Lopez.
Then a moment of controversy when Gerard Moreno appeared to have his shirt pulled by Xabier Etxeita outside of the box and seconds later Moreno seemed to have been tripped up by the Bilbao defender, but referee Prieto Iglesias waved away the protests, much to the anger of RCD Espanyol.
On the 20 minute mark the away side took the lead when De Marcos found Javier Eraso inside the box, his initial shot was saved brilliantly by Lopez, but Eraso took a second bite of the cherry and finished calmly to put his side 1-0 up.
Espanyol had a chance to level the game up minutes later when Pape Diop’s first time shot looked goal-bound but Gorka Iraizoz was equal to shot, clawing it away to keep his side up.
10 minutes before the interval, the home team had another good chance to equalise when Marcos Asensio stepped over a freekick in a very good positition, but the young midfielder could only shoot into the wall.
Two quick goals secure all three points for the home side
Into the second half, Espanyol began to control the tempo of the play in a bid to get themselves back into the game. Five minutes into the second period, Asensio had a glorious chance to tie the game level, but the young Spaniards shot lacked power and was easily handled by Iraizoz.
The Bilbao goalkeeper was called into action moments later when Hernan Perez turned well inside the box and rifled a shot toward the veteran keeper who saved well.
Moreno then had the best chance of the game for the home side when he took the ball out of the air wonderfully but his attempted chip shot was too high and the ball landed on top of the net.
Felipe Caicedo was brought on in place of Marcos Asensio and the Ecuadorian was thrown straight into the deep end as he had his eyes set on the goal, Aymeric Laporte produced an incredible last ditch tackle to put the ball out for a corner.
Abraham stepped up to take the corner and the former FC Barcelona man picked out Pape Diop who powerfully headed the ball into the back of the net to give his side a well deserved equaliser.
Minutes later, Caicedo earned the status ‘super sub’ when he latched onto a pass from Moreno and finished well into the far corner.
In the 72nd minute, Espanyol felt they had scored a third when Caicedo put the ball into the back of the net again, but he and two other Espanyol players were adjudged to have been offside.
Bilbao didn’t trouble the home side for the remainder of the game and Espanyol spurned a brilliant chance in the dying chance when Mamadou Sylla caught Los Leones on the counter attack, but the Senegalese striker saw his shot ricochet back off the post.
That was all she wrote in Barcelona, the win for Los Periquitos moves them up to 12th position while Athletic Club stay in sixth.